Charging and storing camera batteries for a longer life

To make a camera battery last longer, avoid heat, avoid running it flat, store it partly charged and charge it with the correct equipment. Most camera batteries are lithium-ion, and their capacity declines slowly with every charge cycle and every stretch spent hot. Good habits will not reverse that aging, but they can slow it and help you get the most from each battery over its working life.

A battery that drains faster than it used to is not always failing. Cold weather, long video clips, heavy use of the screen, wireless connections and continuous autofocus all draw more power. Before you blame the battery, check how you are using the camera and whether the battery itself has aged. Some cameras show a battery information screen in the menu with a condition or charge count, which gives a clearer picture than guessing.

Charge with the right charger and at a sensible temperature

Use the charger made for your battery, or a replacement that the camera maker or a reputable seller specifies as compatible. A poorly made charger may fail to stop at the right point, and it is a likely source of unwanted heat. Charge in a room-temperature space and keep the charger away from bedding, bags and other materials that trap heat.

Let a battery cool before charging it if it has just come out of a camera that was running hard. A battery that is hot from use or from sitting in sunlight charges less efficiently and ages faster. Many manufacturers list an operating temperature range for their batteries. For charging, the range is often about 32 to 104 °F (0 to 40 °C), depending on the model, and the manual is the right place to check the figures for your model.

Charge the battery when it is low, rather than letting it sit empty for weeks. Most chargers stop automatically once the battery is full, but leaving a battery on the charger for days still keeps it warm and at full charge longer than it needs. Unplug the charger once the indicator shows the battery is full. If a charger becomes hot, makes unusual noises or smells of burning, unplug it and replace it rather than continuing to use it.

Store batteries at a partial charge

Long storage needs a different approach from daily shooting. For a battery you will not use for a few weeks or more, many battery makers suggest storing it at a partial charge, often in the range of about 40 to 60 percent, rather than full or empty. A full battery held at high charge for long periods ages faster, and a fully drained battery can drop to a level where it no longer accepts charge.

Lithium-ion batteries also lose charge slowly while sitting unused, so a battery stored long enough will end up lower than when you put it away. Check stored batteries every few months and top them up to the partial level if they have dropped too far. Write the date on a label or a note so you know when each battery was last checked.

Before storage, make sure the battery is clean and dry, and check the contacts for dust or moisture. If the camera will sit unused for a long stretch, take the battery out of it, because many cameras keep drawing a small amount of power even when switched off. Keep the battery in its case or a separate pouch. If you carry loose batteries in a bag with keys, coins or metal tools, cover the terminals with tape, because a short circuit can damage a battery and create a safety hazard.

Keep batteries away from heat and cold

Heat is the main enemy of batteries. A car dashboard, a sunny window ledge or a bag left in direct sun can heat a battery far beyond comfortable levels, and repeated heat exposure speeds up aging. Keep spares in an inside pocket or a padded case, and do not leave them in a parked vehicle.

Cold has a different effect. Low temperatures reduce how much charge a battery can deliver in the moment, so it may show a lower level on a winter shoot even though it is still good. Carry a spare close to your body to keep it warmer, and expect the displayed charge to recover once the battery warms up. Cold does not usually cause the lasting damage that heat does, but charging is the exception. Do not charge a lithium-ion battery while it is cold, especially below freezing. Let it warm to room temperature first, because charging in the cold can cause permanent damage.

Rotate spares and retire damaged batteries

Rotate spare batteries so that no single one sits unused for years. Use each battery during normal shooting, recharge it, and store the others at a partial level. A battery that is never used can still lose capacity while it sits, and rotating the set keeps the batteries in a more even state.

Stop using any battery that is swollen, hot, leaking or damaged. Swelling can push against the camera door or the case, and a damaged battery is a fire risk. Do not charge it, do not try to open it, and follow your local rules for disposing of lithium batteries at a recycling point. When a battery no longer holds a useful charge after a full cycle, replace it.